This invention relates to lithographic duplicators and particularly to the removal of ink from portions of lithographic duplicating machines. On lithographic duplicators, certain parts of the equipment, for instance the master cylinder and impression cylinders of rotary machines are brought regularly into contact with lithographic printing ink so that, in use, they become stained and require cleaning.
When the ink has partially dried in place it attaches itself quite firmly to whatever surface it finds itself upon and is very difficult to remove. This is especially true with surfaces of anodized aluminum among others but is a problem, to a certain extent, even with polished chromium plated surfaces.
If these surfaces are to function properly they must remain hydrophilic and basically ink-rejecting when wet, and to maintain them in this condition, regular, careful removal of ink stains and residues is essential.
Heretofore various types of cleaning solutions employing principally water dispersible acidic cleaners and the like have been used, but with only modest success, because the dried ink deposits are not found to respond to this kind of treatment except when applied with a great deal of vigor on the part of the user.
It has therefore become a matter of some concern to find a suitable cleaning compound which can be used on lithographic duplicators to clean the surfaces in question in short periods of time and without excessive effort.